The ex-Ross County forward travelled with the Northern Ireland squad to be assessed, although he was not included in O'Neill's matchday squad for the friendly win over Luxembourg on Thursday.

O'Neill has confirmed that Boyce is still looking to get over the hamstring problem as they gear up for a crucial Euro 2020 qualifer against the 2014 world champions tonight in Belfast, although he has not ruled him out of featuring.

"Conor just had a wee bit of a back issue, so we had to monitor him this week and wrap him up in cotton wool.

"If you look at our striking options, Kyle Lafferty and Josh Magennis (who started against Luxembourg) have only just sorted out their club situations and Liam Boyce is dealing with a hamstring injury."

Northern Ireland are currently top of group C with four wins from their first four matches.